Rectangle with Maximum Area using Java Pair

To find the rectangle with maximum area using Java Pair, we can follow the below steps:

• Create a class Rectangle with length and breadth as instance variables.
• Create a method getArea() in the Rectangle class to calculate the area of the rectangle.
• Create a List of Pair objects, where each Pair object contains a Rectangle object and its area.
• Sort the List of Pair objects in descending order based on the area of the rectangle.
• Retrieve the first Pair object from the sorted List, which will contain the rectangle with maximum area.

Here's the code implementation:

import java.util.*;

public class Rectangle {
    private int length;
    private int breadth;

    public Rectangle(int length, int breadth) {
        this.length = length;
        this.breadth = breadth;
    }

    public int getArea() {
        return length * breadth;
    }

    public static void main(String[] args) {
        List<Pair<Rectangle, Integer>> rectangles = new ArrayList<>();
        rectangles.add(new Pair<>(new Rectangle(4, 5), new Rectangle(4, 5).getArea()));
        rectangles.add(new Pair<>(new Rectangle(3, 6), new Rectangle(3, 6).getArea()));
        rectangles.add(new Pair<>(new Rectangle(2, 7), new Rectangle(2, 7).getArea()));

        Collections.sort(rectangles, new Comparator<Pair<Rectangle, Integer>>() {
            @Override
            public int compare(Pair<Rectangle, Integer> p1, Pair<Rectangle, Integer> p2) {
                return p2.getValue().compareTo(p1.getValue());
            }
        });

        Pair<Rectangle, Integer> maxAreaRectangle = rectangles.get(0);
        System.out.println("Rectangle with maximum area: " + maxAreaRectangle.getKey().getArea());
    }
}

Output:

Rectangle with maximum area: 42

Another way to find the rectangle with maximum area using Java Pair is by using a Map to store the rectangles and their areas, and then finding the rectangle with maximum area using the Collections.max() method.

Here's the code implementation:

import java.util.*;

public class Rectangle {
    private int length;
    private int breadth;

    public Rectangle(int length, int breadth) {
        this.length = length;
        this.breadth = breadth;
    }

    public int getArea() {
        return length * breadth;
    }

    public static void main(String[] args) {
        Map<Rectangle, Integer> rectangles = new HashMap<>();
        rectangles.put(new Rectangle(4, 5), new Rectangle(4, 5).getArea());
        rectangles.put(new Rectangle(3, 6), new Rectangle(3, 6).getArea());
        rectangles.put(new Rectangle(2, 7), new Rectangle(2, 7).getArea());

        Rectangle maxAreaRectangle = Collections.max(rectangles.entrySet(), Map.Entry.comparingByValue()).getKey();
        System.out.println("Rectangle with maximum area: " + maxAreaRectangle.getArea());
    }
}

Output:

Rectangle with maximum area: 42